Light metallic truss structure



Oct. 25, 1932. E. J. w. RAGSDALE LIGHT METALLIC TRUSS STRUCTURE FiledMay 29, 1930 FIG.5

INVENTOR. EARL. 1W RAGSDALIE.

A TTORNE Y.

UNITED STATES PATENT OFFICE EARL J. W. RAGSDALE, 0F NORRISTOWN,PENNSYLVANIA, ASSIGNOR TO EDWARD G. BUDD MANUFACTURING COMPANY, OFPHILADELPHIA, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA LIGHT METALLICTRUSS STRUCTURE Application filed May 29,

The invention relates to light metallic trussing, and particularly totrussing of this kind well adapted for use in aircraft construction,such as the ribs of airplane wings.

It is among the objects of my invention to construct such trussing in amanner that it can be very economically constructed and assembled, thatit may be of very light weight, yet strong, durable and capable ofwithstanding the fatiguing and bending draws to which such devices aresubject.

These objects are in large part attained by making the web and chordmembers of thin gauge metal and which may be and preferably is,non-rusting, such as one of the numerous stainless steel alloys and ofsuch cross section as will permit them to be most readily and stronglyjoined together by that most economical of methods of joinder, namely,spot welding. ,7

Other and further objects and advantages will become apparent from thefollowing detailed description in connection with the specificembodiment of the invention shown in the accompanying drawing, forming apart of this specification.

In the drawing,

Fig. 1 is a side elevational view of an airplane rib constructed inaccordance with the invention.

Fig. 2 is a. detail perspective view of one of the web members joiningthe chords.

Fig. 3 is a sectional view taken on the line 33'of Fig. 1.

Fig. 4 is a detail perspective of another form of web member adjacentthe wing spar location.

Fig. 5 is a sectional view taken on the line 5-5 of Fig. 1. I

Fig. 6 is a detail perspective showing the connection of the rear end ofthe chords.

Fig. 7 shows in perspective the gusset and nose piece joining the frontends of the chords.

According to the embodiment of the invention disclosed in the drawing,the upper chord 10 and the lower chord 11 are both formed of channelsection, the channel facing each other and conforming incontour to thecontour of the upper and lower wing surfaces.

The chords are joined by diagonal and ver- 1930. Serial No. 456,993.

tical web member 12, shown in detail in Figs. 2 and 3. These aregenerally of Zsecti0n, the ends of the Z fitting within the channels ofthe chords and are secured to the side walls of the channel by spotwelding. This Z-shape of the web members make possible the dispensingwith gussets while at the same time securing the advantage of the wideanchorage zone between chords and webs, which is obtained by the use ofgussets. To further strengthen and stiffen the web members between theirends, the edges of the webs of the Z are flanged laterally as at 13,thus forming with the Web 14 of the Z the shallow oppositely facingchannels, as clearly appears in Fig. 3.

Adjacent the ends of the rib where the front and rear wing spars areattached to the rib, in place of Z-shaped webs, the angular section webs15 may be used, one of whichis shown in detail in Figs. 4. and 5.

These webs are in general of channel section having their endstelescoped into the channels of the chords and secured thereto by spotwelding. There are two such webs arranged in parallel relation toreceive a spar between them, the bottoms of the channels of the webspresenting toward each other, and intermediate their ends on of the sidewalls of the channel, as 16, is preferably bent out into the plane ofthe bottom to form a wide face for guiding and securing the rib to aspar.

At the rear ends, the chords 10 and 11 approach each other and theirends are arranged in telescoping relation, as shown in Fig. 6, the sidewalls of the channels being secured together by spot welding.

At the front, the chords approach each other but terminate with theirends in spaced cess for receiving an edge strip.

formed by slitting and bending the portion 21 between the slitslaterally to serve as a tab for securing the edge strip in place.

While I have herein described a specific embodiment of my invention asapplied to airplane ribs, it will be understood that I do not intend tobe limited to the precise construction or application so described butonly as required by the spirit and scope of the invention as expressedin the appended claims.

What I elalm is:

1. In a light metallic truss member, opposed channel section chordsjoined together by generally Z-section web members having their oppositearms secured respectively to the opposite side walls of the channels.

2. A web member for light metallic truss structures of generallyZ-section adjacent its ends, and having the arms of the Z intermediateits ends laterally flanged to form with the web of the Z, shallowoppositely facing channels a 3. In a light metallic truss structure,upper and lower chords, a gusset member joining the front ends of thechords to form a round ed apex, a part of said rounded apex of themember being bent laterally to provide a re- In testimony whereof Ihereunto aflix signature.

EARL J. W. RAGSDALE.

